INSTALLATION INSTRUCTIONS

5

OPTIONAL VACUUM ADVANCE LOCKOUT

If you do not want to use the vacuum advance canister

of the MSD Distributor, MSD has supplied the distributor

with a lockout mechanism. The Lockout bolts in the

position of the vacuum canister and will hold the pickup

assembly firmly in place. The installation is easiest with

the distributor out of the engine.

1. Remove the two Allen head screws that hold the

advance canister (Figure 10).

2. Remove the snap ring that holds the magnetic

pickup assembly in place. This is easy to do with

a set of snap ring pliers by straddling one of the

reluctor paddles.

3. Gently lift up on the mag pickup plate and slide the

vacuum canister out.

4. Install the Lockout Plate in place of the canister.

Install the two retaining screws.

5. Install the supplied screw and washer through the

Lockout and tighten. It is important to make sure

the pickup plate is parallel with the housing of the

distributor (Figure 11). If it is cocked or slanted,

the paddles of the reluctor may contact the pickup.

Check the clearance by rotating the distributor shaft.

If necessary, use the supplied shims under the

Lockout hold-down to correctly position the pickup

plate.

Note: If no shims were required, use one beneath

the washer of the Lock-Out Hold Down Screw.

6. After checking the reluctor to pickup clearance,

tighten the Lockout retaining screws and install the

snap ring.

Figure 11 Checking Installation of the Lockout Plate.

Figure 10 Removing the Vacuum Canister.

RELUCTOR

PADDLES

CANISTER

SCREWS

MAG PICK-UP

PLATE

SNAP

RING

VACUUM ADVANCE

Your distributor is equipped with an optional

vacuum advance canister. Vacuum advance

is generally used to improve cruising

economy and driveability, depending on the

application.

The chart in Figure 9 shows the relationship

between engine vacuum and the amount of

ignition timing advance.

To connect the vacuum advance, connect a

vacuum hose from the canister to a ported

vacuum source on the carburetor or throttle

body. Ported vaccum sources are located

above the throttle plates so there will not be

an excessive amount of timing advance at

idle and lower engine speeds.

0

2

4

6

8

10

12

14

12345678

910111213141516

Degrees of Advance

OE Non Adjustable Vac. Adv. 1808

Figure 9 Vacuum Advance and Timing Chart.

7. Install the distributor, rotor and cap. Check the timing when complete.

Note: Do not forget to plug the original vacuum advance hose.